A waste heat recovery boiler may be connected to a gas turbine to effectively use the heat of exhaust gas that is discharged from the gas turbine.
The following PTL 1 discloses a gas turbine plant that includes a gas turbine and a waste heat recovery boiler. The gas turbine plant further includes a steam turbine that is driven by steam generated by the waste heat recovery boiler, a steam condenser that changes the steam, having driven a steam turbine into water, and a low-boiling-point medium Rankine cycle. The low-boiling-point medium Rankine cycle includes: an evaporator that evaporates a low-boiling-point medium, which is a liquid; a turbine that is driven by a low-boiling-point medium, which is evaporated gas; and a condenser that condenses the low-boiling-point medium having driven the turbine. The evaporator of the low-boiling-point medium Rankine cycle evaporates the low-boiling-point medium and changes the steam into water by exchanging heat between a boiling point medium, which is a liquid, and steam that has driven the steam turbine. That is, the evaporator also functions as a steam condenser of the steam turbine.